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.macro bitop, instr
and r2, r0, #7
mov r3, #1
mov r3, r3, lsl r2
save_and_disable_irqs ip
ldrb r2, [r1, r0, lsr #3]
\instr r2, r2, r3
strb r2, [r1, r0, lsr #3]
restore_irqs ip
mov pc, lr
.endm
/**
* testop - implement a test_and_xxx_bit operation.
* @instr: operational instruction
* @store: store instruction
*
* Note: we can trivially conditionalise the store instruction
* to avoid dirting the data cache.
*/
.macro testop, instr, store
add r1, r1, r0, lsr #3
and r3, r0, #7
mov r0, #1
save_and_disable_irqs ip
ldrb r2, [r1]
tst r2, r0, lsl r3
\instr r2, r2, r0, lsl r3
\store r2, [r1]
restore_irqs ip
moveq r0, #0
mov pc, lr
.endm
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